Individual organisms on land and in the ocean sequester massive amounts of the carbon emitted into the atmosphere by humans. Yet the role of ecosystems as a whole in modulating this uptake of carbon is less clear. Here, we study several different mechanisms by which climate change and ecosystems could interact. We show that climate change could cause changes in ecosystems that reduce their capacity to take up carbon, further accelerating climate change. More research on – and better governance of – interactions between climate change and ecosystems is urgently required.

The politics of the United Nations aims at sustainable development (i.e., development that can continue with future generations). Andreas Losch has recently proposed to expand our current notion of sustainability to what he calls ‘planetary sustainability’, and he has urged an ethics of planetary sustainability. This comment article discusses these proposals. The proposed conceptual change is assessed, drawing on desiderata suggested by Carnap. To the extent to which the current notion of sustainability has excluded consideration of outer space, we gain in simplicity. To the extent to which it has been unclear about this issue, we gain in exactness. The proposed concept is fruitful because it points to important considerations, in particular if there are extra-terrestrial beings that share moral status with human beings. But to some extent this fruitfulness requires a clear deviation from the anthropocentric outlook of our current notion of sustainability, and costs regarding similarity arise. As far as an ethics of sustainability is concerned, we certainly need to address ethical issues that arise in relation to outer space. However, the notion of planetary sustainability is not likely to figure prominently in related thoughts because the notion of sustainability is not a key concept in known ethical theories.

The world agreed to achieve 17 Sustainable Development Goals by 2030. Nine planetary boundaries set an upper limit to Earth system impacts of human activity in the long run. Conventional efforts to achieve the 14 socio-economic goals will raise pressure on planetary boundaries, moving the world away from the three environmental SDGs. We have created a simple model, Earth3, to measure how much environmental damage follows from achievement of the 14 socio-economic goals, and we propose an index to track effects on people's wellbeing. Extraordinary efforts will be needed to achieve all SDGs within planetary boundaries.

Since the earliest stages of international climate policy, carbon dioxide (CO2) has been framed and widely accepted as a problem that needs to be solved by reducing its amount in the atmosphere. In principle this is a correct and relevant starting point for efforts to decarbonize societies. At the same time, however, the unquestioned and one-sided framing of CO2 as a problem has significantly biased the strategies for tackling climate change. We introduce the origins, meanings and implications of one-sided framing of CO2 in climate policy. We also discuss how alternative framings could impact policymaking and eventually our capacity to mitigate climate change. We introduce a paradox: framing CO2 as a problem often translates into policies that hamper the implementation of technologies to decrease the amount of CO2 emitted into the atmosphere. We suggest that plurality in framing CO2 could lead to innovative ways and strategies to combat climate change.

Sustainable access to outer space is increasingly threatened by growing orbital clouds of satellites and debris. A boom in competitively priced commercial rocket launches has lowered prices, prompting satellite operators to begin deploying thousands of satellites. Six decades ago, ‘hard law’ international treaties established governance for outer space designed for the few governmental space programmes. Today, non-governmental commercial entities are operating under voluntary ‘soft law’ rules of the road that expose the deficiencies of the original treaties to empower regulatory supervision of the expanding commercial orbital presence. This paper suggests how a ‘sustainable’ system of governance, required for sustainable space access and exploration, may be promoted by increasing the costs of non-compliance.